Abstract: A communication satellite cellular coverage pointing correction using uplink beacon signal is provided. A ground-based beacon transmits a monopulse tracking signal or a Traveling Wave Coupler (TWC) tracking signal to a specialized tracking feed section located within each uplink and downlink antennae of a satellite. From the monopulse or TWC tracking signal, a pointing correction is determined for each reflector, for example, the angle off boresight and the angle between the present beam direction and the target direction. Each reflector is then gimbaled to re-point the reflector to the target area. In this way, both uplink and downlink antennae are provided with closed-loop control over antenna pointing.

Abstract: A multiple access communications system includes a communications unit, such as satellite or a mobile link base station, and an antenna disposed thereon. The antenna has the capability to direct an antenna beam at a selected user on a packet by packet basis thereby reducing the latency, buffering, and non-uniform gain distribution associated with conventional transmission systems.

Abstract: A multi-band reflector antenna has a main reflector defining a prime focus and a frequency selective surface (FSS) sub-reflector defining an image focus. One or more transmitter or receiver feeds are provided at each of the prime focus and image focus. In one application as a ground satellite terminal, the antenna supports Ka-band two-way broadband Internet access bundled with multi-satellite Ku-band direct broadcast television service (DBS).

Abstract: A multi-band reflector antenna has a main reflector defining a prime focus and a frequency selective surface (FSS) sub-reflector defining an image focus. One or more transmitter or receiver feeds are provided at each of the prime focus and image focus. In one application as a ground satellite terminal, the antenna supports Ka-band two-way broadband Internet access bundled with multi-satellite Ku-band direct broadcast television service (DBS).

Abstract: A multi-band reflector antenna has a main reflector defining a prime focus and a frequency selective surface (FSS) sub-reflector defining an image focus. One or more transmitter or receiver feeds are provided at each of the prime focus and image focus. In one application as a ground satellite terminal, the antenna supports Ka-band two-way broadband Internet access bundled with multi-satellite Ku-band direct broadcast television service (DBS).

Abstract: A dual phased array payload (100) for use onboard a communications satellite is disclosed. The payload includes one or more phased array receive antennas (102-108) including numerous individual receiving elements distributed in a predetermined configuration. Each of the individual radiating elements is selectively adjustable in amplitude and phase to achieve scanning beams for receiving information transmitted from the ground in an uplink beam. The payload includes a packet switch (114) connected to the phased array receive antennas (102-108). The packet switch (114) includes a set of inputs and a set of outputs. The set of inputs are selectively connectable to the set of outputs. The payload (100) includes one or more phased array transmit antennas (120-126) connected to the packet switch (114). The phased array transmit antennas (120-126) include numerous individual radiating elements distributed in a predetermined configuration.

Abstract: An adaptive nulling communication system for nulling undesired signals from communication signals in multiple separate and distinct coverage areas is disclosed. The adaptive nulling communication system includes a phased array antenna having multiple receiving elements to form a single aperture for receiving multiple signals. A first set of beam forming networks coupled to the phased array antenna forms the multiple separate and distinct coverage areas. A distribution network coupled to the first set of beam forming networks distributes the signals received from these coverage areas. A nulling processor having a second beam forming network coupled to the distribution network weights and adjusts the second beam forming network in response to the undesired signals to null these undesired signals from the communication signals.